1. Field
The following description relates to a virtualization technology for concurrently operating a plurality of operating systems, and a scheduling technology of achieving the real time operation.
2. Description of the Related Art
Virtualization is a technology allowing multiple virtual machines having their own operating systems to operate in a single host computer.
According to virtualization, the host computer executes a virtual machine monitor, and the executed virtual monitor creates a plurality of virtual machines. A virtual machine (VM) is an implementation of a machine (i.e., a computer) that executes programs like a physical machine. The VM may be software or a system-on-chip (SOC). One use is to support a real-time operating system at the same time as a high-level operating system (OS), such as Linux or Windows. The virtual machines created by the host computer can run concurrently, and each of the virtual machines has its own virtual hardware resources. For example, each of the virtual machines may have one or more Virtual Central Processing Unit (VCPU), and may occupy a part of the memory of the host computer.
Scheduling in a virtualization environment is achieved in a VCPU unit; as such, the conventional scheduling is achieved only based on a Time Quantum (time limit) allocated to each VCPU. Accordingly, this causes a limitation on supporting real-time functionality in the system. Although virtualization has been used in server technology, for each server application, system resources were equally used among VMs; as such, the conventional technology is not usable in consumer electronics having real-time processing needs.